In recent years the use of plastic, disposable pipette tips has expanded rapidly to the point that there now are literally millions of these tips used in the United States each year. The plastic tips are used with pipettors, and in most applications each tip is used once and then disposed of so as to avoid contamination and eliminate the need for cleaning of the tips. Thus, a single pipettor will be used with hundreds and even thousands of disposable tips in the course of a week.
Disposable, plastic pipette tips are typically packaged for shipment and for use and storage in rectangular or box-like containers or "racks" in which the tips are oriented vertically and positioned in a bore or opening in the rack with their open upper ends ready to receive the pipettor. U.S. Pat. Nos. 5,057,282, 4,349,109, 4,130,978, 3,937,322 and 3,853,217 are typical of various pipette tip racks or storage containers which can be used to package and ship the pipette tips and act as racks for dispensing of the tips. Most typically, these racks are loaded by hand in a relatively tedious operation. Since there typically will be 96 to 250 pipette tips per rack or layer in multi-layer containers, hand loading of the tips into the containers adds a significant cost to the disposable tips, which often have a sales price of only a few cents per tip. Moreover, handling of the tips, even with rubber gloves, exposes them to contamination, which for some tips will require subsequent sterilization while the tips are in the racks.
Automated packaging or loading of pipette tips, or other small tubular or elongated objects such as test tubes, into storage racks presents a difficult problem because of the number of the objects, their small size, their light weight and the close spacing which is required. Nevertheless, an automated packaging or rack-loading technique would be highly desirable in terms of both costs savings and contamination reduction.
Accordingly, it is an object of the present invention to provide an apparatus and method for automated loading of tubular or rod-like objects, and particularly pipette tips, into a shipping and storage container or rack.
It is a further object of the present invention to provide an apparatus and method for automatic loading of pipette tips which is highly reliable, easily adaptable to a variety of pipette tip sizes, requires minimum maintenance, and will operate at relatively high speed.
The apparatus and method of the present invention have other objects and features which will be apparent from or are set forth in more detail in the accompanying drawing and description of the Best Mode of Carrying Out the Invention.